Money Blog - How discounted is that note really? Part 2

Okay, time for part 2.  To recap, the scenario from Part 1 is as follows:  


I came across a note for sale.  The terms of the note are as follows:

Original balance: $6,000

Unpaid balance as of June 2: $4,560

Term: 5 years

Interest Rate: 0

Payments: $100 per month

If I buy it, make the purchase on June 2, and the first payment I'll receive will be the July payment.

Every February, the borrower pays off $1,000 in order to accelerate the note paydown.


If I buy the note for its face value ($4,560), what will my yield (or Return On Investment, or the Internal Rate of Return of the deal) be?

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